| // Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| import 'package:analyzer/dart/ast/ast.dart'; |
| import 'package:analyzer/dart/ast/visitor.dart'; |
| |
| import '../analyzer.dart'; |
| |
| const _desc = r"Don't specify the `late` modifier when it is not needed."; |
| |
| const _details = r''' |
| |
| **DO** not specify the `late` modifier for top-level and static variables |
| when the declaration contains an initializer. |
| |
| Top-level and static variables with initializers are already evaluated lazily |
| as if they are marked `late`. |
| |
| **BAD:** |
| ```dart |
| late String badTopLevel = ''; |
| ``` |
| |
| **GOOD:** |
| ```dart |
| String goodTopLevel = ''; |
| ``` |
| |
| **BAD:** |
| ```dart |
| class BadExample { |
| static late String badStatic = ''; |
| } |
| ``` |
| |
| **GOOD:** |
| ```dart |
| class GoodExample { |
| late String goodStatic; |
| } |
| ``` |
| '''; |
| |
| class UnnecessaryLate extends LintRule { |
| UnnecessaryLate() |
| : super( |
| name: 'unnecessary_late', |
| description: _desc, |
| details: _details, |
| group: Group.style); |
| |
| @override |
| void registerNodeProcessors( |
| NodeLintRegistry registry, LinterContext context) { |
| var visitor = _Visitor(this); |
| registry.addFieldDeclaration(this, visitor); |
| registry.addTopLevelVariableDeclaration(this, visitor); |
| } |
| } |
| |
| class _Visitor extends SimpleAstVisitor<void> { |
| final LintRule rule; |
| |
| _Visitor(this.rule); |
| |
| @override |
| void visitFieldDeclaration(FieldDeclaration node) { |
| if (node.isStatic) { |
| _visitVariableDeclarations(node.fields); |
| } |
| } |
| |
| @override |
| void visitTopLevelVariableDeclaration(TopLevelVariableDeclaration node) { |
| _visitVariableDeclarations(node.variables); |
| } |
| |
| void _visitVariableDeclarations(VariableDeclarationList node) { |
| if (node.lateKeyword == null) { |
| return; |
| } |
| |
| for (var variable in node.variables) { |
| if (variable.initializer != null) { |
| rule.reportLint(variable.name); |
| } |
| } |
| } |
| } |